Problems with my 4l60e!!! need help!
Thread Starter
TECH Enthusiast
Joined: Sep 2009
Posts: 565
Likes: 0
From: Decatur, IN
Problems with my 4l60e!!! need help! So last year I wrecked my bird.
spent a lot of time and money to rebuild the body on it
Went to go out and drive it for the first time in a year and a half this weekend and found some problems that I didn't know I had.
after the wreck, the tranny pan was a little smashed from going over a couple smaller rocks, not completely trashed but enough damage that I felt like I need to replace it.
So I put a new pan on it.
before the wreck the trans shifted firm in every gear, worked exactly like it should. was rebuilt about 20k miles ago and has a trans-go shift kit and different clutches put in, anyways it shifted just fine. stock stall..
when I drive it now, first gear shifts really early and very slow going into second gear. this is lets say normal driving (like 20-30% throttle) it use to shift firm where you actually felt it
second gear to third shifts a little better, but still not (firm) at all like it use to be.
If I manually shift it it does not make a difference, and if you try to go over 60-70% throttle it just revvs in 2nd and third.
if you are going lets say 70-80mph on the highway in third gear the converter does not downshift or (flash up) so to say it stays in gear.
if anyone sat to read all this please give me some input. I was hoping it might just be something simple like a broken sensor or something but I havent dug into it yet was pretty bummed after the first drive
-Thanks Zac
spent a lot of time and money to rebuild the body on it
Went to go out and drive it for the first time in a year and a half this weekend and found some problems that I didn't know I had.
after the wreck, the tranny pan was a little smashed from going over a couple smaller rocks, not completely trashed but enough damage that I felt like I need to replace it.
So I put a new pan on it.
before the wreck the trans shifted firm in every gear, worked exactly like it should. was rebuilt about 20k miles ago and has a trans-go shift kit and different clutches put in, anyways it shifted just fine. stock stall..
when I drive it now, first gear shifts really early and very slow going into second gear. this is lets say normal driving (like 20-30% throttle) it use to shift firm where you actually felt it
second gear to third shifts a little better, but still not (firm) at all like it use to be.
If I manually shift it it does not make a difference, and if you try to go over 60-70% throttle it just revvs in 2nd and third.
if you are going lets say 70-80mph on the highway in third gear the converter does not downshift or (flash up) so to say it stays in gear.
if anyone sat to read all this please give me some input. I was hoping it might just be something simple like a broken sensor or something but I havent dug into it yet was pretty bummed after the first drive
-Thanks Zac
Moderator
Joined: Aug 2010
Posts: 7,323
Likes: 529
From: Ann Arbor, MI
Since the trans internals did not change, lets assume the trans really is OK.
A couple things come to mind:
* Fluid filter - when you replaced the pan did you replace the filter? Is the right kind of filter firmly in place?
* Speedometer - is your speedometer reading correctly.
* Sensors - the MAF, TPS and MAP all affect the trans operation. Make sure they are working properly.
* Codes - use a good scanner to check for hidden codes.
If none of that helps, hook up a trans pressure gauge. I think your trans pressure is very low, either due to a filter problem or sensor problem. You can buy a trans pressure gauge on ebay for $45 shipped or have a local (non-chain) trans shop hook one up and do some quick tests.
Don't drive around much with a slipping trans as that will quickly wear out the frictions.
A couple things come to mind:
* Fluid filter - when you replaced the pan did you replace the filter? Is the right kind of filter firmly in place?
* Speedometer - is your speedometer reading correctly.
* Sensors - the MAF, TPS and MAP all affect the trans operation. Make sure they are working properly.
* Codes - use a good scanner to check for hidden codes.
If none of that helps, hook up a trans pressure gauge. I think your trans pressure is very low, either due to a filter problem or sensor problem. You can buy a trans pressure gauge on ebay for $45 shipped or have a local (non-chain) trans shop hook one up and do some quick tests.
Don't drive around much with a slipping trans as that will quickly wear out the frictions.
Teching In
Joined: Sep 2011
Posts: 8
Likes: 0
Do you have HPtuners or any kind of logging software where you can watch your torque converter commands and TCC slip speeds? or even better, line pressure?
if not, this would be really hard to diagnose. From what i have learned a "shift kit" can only apply available line pressure, it dose't just pull extra line pressure outa thin air, the force motor has 100% control over that. if you DO have hp tuners and your force motor is a higher output motor you will need to reduce the values on the force motor in 10% increments until you receive the desired shift firmness.
glad to hear you survived the impact, what all on or around the motor was damaged? Remember if you have a stock intake its composite, might look A-OK in front and have a gaping hole where your MAP used to be, or the itty bitty wires in your MAF could have become broken. TPS is on the side of the TB, wires could have been smushed or the body itself (on the tps) could be cracked. but your issue to me sounds like line pressure. post a log if you can!
if not, this would be really hard to diagnose. From what i have learned a "shift kit" can only apply available line pressure, it dose't just pull extra line pressure outa thin air, the force motor has 100% control over that. if you DO have hp tuners and your force motor is a higher output motor you will need to reduce the values on the force motor in 10% increments until you receive the desired shift firmness.
glad to hear you survived the impact, what all on or around the motor was damaged? Remember if you have a stock intake its composite, might look A-OK in front and have a gaping hole where your MAP used to be, or the itty bitty wires in your MAF could have become broken. TPS is on the side of the TB, wires could have been smushed or the body itself (on the tps) could be cracked. but your issue to me sounds like line pressure. post a log if you can!
